A traditional way of including a buffer in a chewing gum formulation is by adding the buffer in the chewing gum formulation only after the gum base has been prepared. This may be done by adding a buffer while mixing an insoluble gum base matrix with a soluble bulk portion of the chewing gum formulation, or by adding buffer to a bulk portion and then mixing the bulk portion with a gum base matrix. In the alternative, this may also be done by adding buffer in a compressed formulation or by adding buffer to an outer coating of a chewing gum.
WO 02/102357 describes a coated chewing gum formulation suitable for rapid release of nicotine to a human subject by the addition of a buffer in the chewing gum formulation. One of the ways suggested in order to include the buffer in the chewing gum formulation is by adding the buffer to the coating of a final chewing gum core. Also, it is exemplified that in addition to including buffer to the coating of the final chewing gum core, a buffer may additionally be added together with a pre-prepared gum base (Cafosa Gum S/A) and other ingredients in the chewing gum formulation. However, the document does not disclose or suggest means for obtaining a high pH level for longer periods and means for obtaining a higher loading capacity of buffer without compromising the stability of the final chewing gum. Furthermore, the document is silent about how to obtain a buffered chewing gum without compromising the quality of the chewing gum, such as the texture, sensorial acceptance or taste of alkaline buffer in the chewing gum.